Piston



Aug. l, 1939. A. v. NlcoLLE PISTON Filed Aug. 29, 1938 E9n f.

4 m Wk m m` v Patented Aug. `l, 1939 UNITED STATES PISTON A rthurVilleneuve Nicolle, Twickenham, England Application August 29,

In Great Britain 7 Claims.

y"This invention relates to pistons for internal combustion engines, andhas for its object to provide improvements in the construction ofthepistons which enables modern requirements as to lightness to befullledconsistent with strength and the dissipation of heat.

The invention consists in a piston formed from thin metal, such as thinsteel, and having a chamber therein for containing a cooling me- 10dium, such as sodium or sodium salt, and wherer in means is providedextending between the crown and the gudgeon pin bosses for transmittingthe force imposed upon the piston, characterized by the feature that theportion or area of the crown to which the said means is connected, has ahighly heat conducting insertion associated therewith for dissipatingthe heat in said zone.

The invention also consists in a piston according to the precedingparagraph, wherein the centre of the crown of the piston is supportedfrom the bosses or boss region of the piston as by struts and/or aninner shell or lining, and the interior of the piston adjacent the crownisformed with a chamber or receptacle for containing a cooling medium,such as a readily fusible salt or metal, for example sodium orsodium-salt, ,in which receptacle there protrude's anv element which ismade from highly heat conducting ma- I terial, such as copper,aluminium'or nickel, and

is in contact with the centre of the crown.

This element, therefore, and which may be inv the form of a dis'c andmay be hollow and contain a. body of the coolant, serves to dissipatelheat from the centre of the crown.

Conveniently, the cooling chamber is formed between the piston head andan insert in the form offa dome-shaped stamping or pressing, the

base of which is secured to the inside of the head 40 in thev region ofthe ,gudgeon pin bosses, while the apex extends to the centre of thecrown and is' secured through the medium of the element or discabovementioned.

The reference above, land hereafter to thin metal or thin steel", isintended to cover a piston the thickness of the skirt, of which does1938, Serial No. 227,423 September 30, 1937 (Cl. 12S-176) there issecured within the interior of a piston which may be formed from thinsteel, a lining a which may be in the form of a thin pressing or.

stamping of suitable metal .such as steel, and which forms with theinside surfaces of the piston, including the crown b thereof, avreceptacle c for containing a cooling medium constituted by a readilyfusible salt ormetal, such as for example, sodium or sodium salt; andwithin the piston as shown' in the case of Figure 1,y so as to protrudeinto the cooling receptacle, there is provided an element d which issecured to the centre of the crown of the piston on the inside thereof,and is formed from a highly heat conducting metal, such as for example,copper, aluminium or nickel.

l'The lininga may conveniently, be of domed form, and have its basesecured to the inside surfaceof the piston head in the region of thegudgeon 'pin bosses e, while its apex extends within the piston to thecentre of the crown thereof', between`which and the apex of the dome thesaid element is secured so as in the case of Figures 1,

2 and 3, to be in contact with the crown b, and

so -as to protrude into vthe cooling chamber, the element beingconveniently in the formof 'a thin disc having its peripheral portionextending into the cooling chamber as shown, or it may be` formed of ahollow disc containing a body of the coolant. Alternatively, and asshown in Figure 4, the heat'dissipating disc d may be secured to theoutsides'urface of the lining, in the region thereof where the lining isin contact with the crown, and be secured between the lining and anarchpiece f containing the g'udgeon pin bosses.

1.A piston comprising a head,` a skirt and gudgeon pin bosses carried bythe skirt, the piston beingformed from thinfmetal, such as thin steel,and having an interior chamber containing a .cooling medium, such assodium or sodium salt, means extending between the piston crown and thegudgeonfpin bosses for transmitting'to the piston skirt the forcesimposed upon the piston crown, and a highly heat conducting insertionconnected with that portion or area of the crown to ,which the' saidforce transmittingY means is connected, the said insertion serving todissipate heat from said portion or area of the crown.

2. A piston comprising a head, a skirt and gudgeon pin bosses carried bythe skirt, the pislton being formed from thin metal, suck. as thin steeland having an interior chamber containing a cooling medium, such assodium or sodium 55' salt, strut means extending between the innersurface of the piston crown and the gudgeon pin bosses to aord a supportfor the central portion of the crown, and an4 element located betweenthe crown and the said strut means so as to contact with both and'protrude into the cooling chamber, the said element being of a highlyheat conducting material and serving to dissipate heat from the centreof the crown.

3. A piston comprising a head, a skirt and gudgeon pin bosses carried bythe skirt,.the piston being formed from thin metal, such as thin steel,

a cup member secured within the piston interior so as to forma closedchamber therein, the walls of which .include the inner surface of thepiston crown, cooling means such as sodium or sodium salt within saidchamber, a reinforcing member secured within the piston interior so asto connect the gudgeon pin bosses in the piston skirt and having aportion extending to the centre of the piston crown, and a highly heatconducting insertion associated with the said reinforcing member so asto dissipate heat from the central crown portion.

4. A piston as claimed in claim 3, wherein said heat conductinginsertion consists of a metallic disc located between the centralportion of the piston crown and the adjacent portion of the reinforcingmember, so that the disc is in contact with both, and so that theperipheral portion of the disc extends into the cooling chamber.

5. A piston as' claimed in claim 3, wherein the heat conductinginsertion is in the form of a thin metallic disc located within thecooling chamber, and the said cup member is of dome shape with itsperiphery secured to the piston skirt and its apex extending to thecentre of the piston crown.

6. A piston as claimed in claim 3, wherein the heatconducting insertionis in the form of a thin metallic disc in contact with the in nersurface of the piston crown and with the said cup member.

'1. A piston as claimed in claim 3, wherein the reinforcing member is ofarch shape with its apex situated opposite the central portion of thepiston crown, andthe said cup member is of dome shape conforming to theshape of the arch piece which is disposed exteriorly of the said chamberand in contact-l with the said dome.

` VILLENEUVE NICOLIE.

